The Queensland Government has gained the support of education groups for plans to overhaul the senior school assessment system.

But the moves have been criticised by the state’s LNP opposition.

The planned changes include replacing the current OP university entrance score with the Australian Tertiary Admissions Rank (ATAR), requiring syllabuses for 80 senior high school subjects to be rewritten.

The reforms include more external exams, so that senior subject results will be based on three school-based and one external assessment, which will be weighted differently depending on the subject.

Additionally, an English subject will be compulsory for students to receive their Queensland Certificate of Education when the changes take effect.

The Palaszczuk Government has postponed the changes to 2019, but the previous LNP government intended to make the same changes by 2017.

Queensland Teachers Union vice-president Sam Pidgeon said the original timeline was pretty ambitious.

“I'm seeing it as an opportunity to ensure that teachers have got the best-resourced, best-prepared approach to this,” she told reporters.

“There won't be many teachers or school leaders or, I dare say, parents across the state who will be concerned about this delay.”

Queensland Curriculum Assessment Authority CEO Chris Rider said rewriting 80 courses simultaneously is a tough task.

“We need not rush it ... we need to make sure that what we're doing for young people in 2020 is absolutely the right thing for the next 20 years in Queensland,” he said.

The Catholic Education Commission says it is glad for the extra time.

P&Cs Queensland president Gayle Walters said it would let teachers engage with the new curriculum.

“As a parent, I'd like to say that we are extremely confident that the [Education] Minister's decision here is the best one for the education of the children,” she said.

Independent Schools Queensland said the complexities of the system made it especially important to enact the changes properly.